The objectives of this proposal are to learn more about the biochemical sequence of events in the formation and release of SRS in the cat paw induced by 48/80; to compare the biological sequence of events in the cat paw system with those reported in other systems as a basis for determining the usefulness of 48/80 as a model antigen-antibody reaction that can be used to study SRS formation and release; and to explore various procedures and compounds that will stimulate the release of SRS. Also, we have been attempting to purify SRS using high pressure liquid-liquid chromatography. BIBLIOGRAPHIC REFERENCES: J.A. Chan, M. Nagasawa, C. Takeguchi and C.J. Sih, On agents favoring prostaglandin F formation during biosynthesis. Biochemistry, 14, 2987 (1975).